Tuesday, April 7, 2015

All About WOOL

Caution: nerd alert! (Admit it, if you are a knitter or crocheter you probably have a bit of a nerdy side)

If you're not already a yarn snob, you are about to learn some good reasons to become one. Why? The kind of fiber your yarn is made of makes a huge difference!

Image from CSIRO

Check out this electron microscope image of a wool fiber. Wool is a natural protein fiber, similar to human hair in that it's made of a keratin-like protein. This fiber has some amazing properties:

Felting: When wool is agitated with heat and moisture, the scales of the edges of wool fibers interlock, creating a durable fabric. Felting is great for creating warm, durable projects such as clogs, mittens, and bags. However, it can be a bummer when a wool garment accidentally is thrown in the washing machine, since felting shrinkage is irreversible.

Copyright Fiber Trends

Flexibility and Durability: the molecular structure of each wool fiber is a coiled spring, making the fiber very elastic. This flexibility also makes the fiber more durable: a wool fiber can be bent back on itself more than 20,000 times without breaking, compared to about 3,000 times for cotton and 2,000 times for silk.

Water Absorbency: Wool is considered a hygroscopic fiber, meaning it takes up moisture in vapor form. Tiny pores in the fiber will take up moisture from its environment, and also release moisture in drier conditions. Wool is especially comfortable to wear because it keeps a layer of air next to the skin. As wool absorbs moisture, it actually generates heat! The hydrogen bond of water is broken and chemically reacts with molecules of wool to generate heat. This makes wool ideal for absorbing sweat and providing protection against hypothermia. For these reasons wool is worn in desert regions of the world where it's hot in the daytime and cold at night.

Resistance to Flame: Wool blankets can be used to extinguish small fires because wool is self-extinguishing. Wool contains moisture in every fiber, so it will not support combustion.

Takes Dye Beautifully: Wool absorbs dye into the inner core of the fiber, where a chemical reaction occurs making the color change permanent except under extreme conditions. Wool is an amphoteric, meaning the fiber takes in both acidic and basic dyes. This means that wool can be dyed in an incredibly wide array of beautiful colors!